package com.rabbit.rpc;

/**
 * @author CUIJIAJUN
 * @date   2017年2月15日
 * 
 */

import java.security.MessageDigest;  
  

import com.rabbit.RabbitFactory;
import com.rabbitmq.client.AMQP;  
import com.rabbitmq.client.AMQP.BasicProperties;  
import com.rabbitmq.client.Channel;  
import com.rabbitmq.client.Connection;  
import com.rabbitmq.client.ConnectionFactory;  
import com.rabbitmq.client.QueueingConsumer;  
//RPC调用服务端  
public class RPCServer {  
    private static final String RPC_QUEUE_NAME = "rpc_queue";  
    public static void main(String[] args) throws Exception {  
        //• 先建立连接、通道，并声明队列  
        Connection connection = RabbitFactory.creatConnection();  
        Channel channel = connection.createChannel();  
        channel.queueDeclare(RPC_QUEUE_NAME, false, false, false, null);  
        //•可以运行多个服务器进程。通过channel.basicQos设置prefetchCount属性可将负载平均分配到多台服务器上。  
        channel.basicQos(1);  
        QueueingConsumer consumer = new QueueingConsumer(channel);  
        //打开应答机制autoAck=false  
        channel.basicConsume(RPC_QUEUE_NAME, false, consumer);  
        System.out.println(" [x] Awaiting RPC requests");  
        while (true) {  
            QueueingConsumer.Delivery delivery = consumer.nextDelivery();  
            BasicProperties props = delivery.getProperties();  
            BasicProperties replyProps = new BasicProperties.Builder()  
                    .correlationId(props.getCorrelationId()).build();  
            String message = new String(delivery.getBody());  
            System.out.println(" [.] getMd5String(" + message + ")");  
            String response = getMd5String(message);  
            //返回处理结果队列  
            channel.basicPublish("", props.getReplyTo(), replyProps,  
                    response.getBytes());  
            //发送应答   
            channel.basicAck(delivery.getEnvelope().getDeliveryTag(), false);  
        }  
    }  
    // 模拟RPC方法 获取MD5字符串  
    public static String getMd5String(String str) {  
        MessageDigest md5 = null;  
        try {  
            md5 = MessageDigest.getInstance("MD5");  
        } catch (Exception e) {  
            System.out.println(e.toString());  
            e.printStackTrace();  
            return "";  
        }  
        char[] charArray = str.toCharArray();  
        byte[] byteArray = new byte[charArray.length];  
  
        for (int i = 0; i < charArray.length; i++)  
            byteArray[i] = (byte) charArray[i];  
        byte[] md5Bytes = md5.digest(byteArray);  
        StringBuffer hexValue = new StringBuffer();  
        for (int i = 0; i < md5Bytes.length; i++) {  
            int val = ((int) md5Bytes[i]) & 0xff;  
            if (val < 16)  
                hexValue.append("0");  
            hexValue.append(Integer.toHexString(val));  
        }  
        return hexValue.toString();  
    }  
}  